CN111969247A - Solid electrolyte for in-situ protection of metal lithium cathode and preparation method thereof - Google Patents
Solid electrolyte for in-situ protection of metal lithium cathode and preparation method thereof Download PDFInfo
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- 239000007784 solid electrolyte Substances 0.000 title claims abstract description 43
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 41
- 238000011065 in-situ storage Methods 0.000 title claims abstract description 30
- 229910052751 metal Inorganic materials 0.000 title claims description 16
- 239000002184 metal Substances 0.000 title claims description 16
- 238000002360 preparation method Methods 0.000 title abstract description 9
- 239000005518 polymer electrolyte Substances 0.000 claims abstract description 22
- 229910003002 lithium salt Inorganic materials 0.000 claims description 33
- 159000000002 lithium salts Chemical class 0.000 claims description 32
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- 238000000034 method Methods 0.000 claims description 11
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- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims description 2
- 229910003473 lithium bis(trifluoromethanesulfonyl)imide Inorganic materials 0.000 claims description 2
- QSZMZKBZAYQGRS-UHFFFAOYSA-N lithium;bis(trifluoromethylsulfonyl)azanide Chemical compound [Li+].FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F QSZMZKBZAYQGRS-UHFFFAOYSA-N 0.000 claims description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 claims description 2
- 229920005569 poly(vinylidene fluoride-co-hexafluoropropylene) Polymers 0.000 claims description 2
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- 150000003384 small molecules Chemical class 0.000 claims 1
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- 239000007788 liquid Substances 0.000 description 2
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- 238000002844 melting Methods 0.000 description 1
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- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0082—Organic polymers
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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- Physics & Mathematics (AREA)
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Abstract
The invention belongs to the technical field of polymer electrolytes, and particularly relates to a solid electrolyte for in-situ protection of a metallic lithium cathode and a preparation method thereof.
Description
Technical Field
The invention belongs to the technical field of polymer electrolytes, and particularly relates to a solid electrolyte for in-situ protection of a lithium metal cathode and a preparation method thereof.
Background
The development of electric vehicles and intelligent energy storage promotes the rapid development of high-specific-energy secondary lithium batteries. Metallic lithium negative electrodes are receiving increasing attention from researchers of high specific energy secondary lithium batteries due to their high theoretical energy density and low reduction potential. A secondary lithium battery system using a lithium metal negative electrode and a high-voltage ternary positive electrode is also the most promising next-generation lithium battery. However, the conventional lithium ion battery uses a liquid organic electrolyte which contains a toxic, volatile and low-ignition-point organic solvent, which brings potential safety hazards such as flammability and the like to the lithium ion battery. The solid lithium ion battery has the advantages of low reactivity between the electrolyte and electrodes, high energy density, metamerism, high safety and the like, so that the development of the all-solid polymer electrolyte can not only reduce the cost of the battery, but also ensure the safety of the battery in the use process.
At present, in order to improve the performance of the solid-state battery, researchers use lithium salts which are basically large anion lithium salts, the lithium salts are beneficial to improving the ionic conductivity, but the lithium metal negative electrode has no protection effect, so that the current solid-state battery matched with the lithium metal negative electrode has poor cycle performance and cannot meet the actual application requirements.
Compared with a carbon negative electrode, the SEI film of the metal lithium negative electrode is easy to crack due to lithium dendrite, and meanwhile, the exposed metal lithium can generate side reaction with an electrolyte, so that the design of the SEI film of the metal lithium negative electrode is very important in the practical application process. In the practical application process, the fragmentation and reconstruction of an SEI film are inevitable, so a sustainable SEI environment has very important significance for a lithium metal negative electrode, for example, patent application No. CN201811625539.0 discloses an interface modification method for a lithium metal negative electrode of a solid lithium battery, a modification layer is formed on the surface of the lithium metal by adopting a mode of in-situ generation of a gel polymer, and a precursor of the gel polymer contains a 1,3 dioxolane solvent (DOL) capable of in-situ ring-opening polymerization under the action of a specific lithium salt and also contains a plurality of additives capable of forming a stable SEI film on the surface of the lithium metal. The precursor can be subjected to in-situ polymerization on the surface of the metal lithium electrode in a simple heating mode to form a DOL oligomer modified buffer layer with viscoelasticity, and the scheme can improve the interface physical contact between the metal lithium electrode and a solid electrolyte, so that the interface impedance is reduced. Meanwhile, a stable SEI film can be formed on the surface of the metal lithium, and the cycle performance of the solid lithium battery is favorably improved.
At present, patent application No. cn202010179504.x discloses a polymer solid electrolyte based on the principle of bulk plasticization and a method for preparing the same. The mass plasticizing polymer electrolyte is prepared by carrying out photopolymerization on dithiol and dienyl ether according to different proportions to generate linear polyether thioether polymers with different molecular weights, and then using a part of polymers to be terminated by monoalkenyl ether as a polyether thioether mass plasticizer; the other part of the polymer and the polyene cross-linking agent are subjected to in-situ cross-linking polymerization in a mixture of the polyether thioether bulk plasticizer and the small molecular lithium salt according to a certain proportion. The bulk plasticized polymer solid electrolyte prepared by the invention has high lithium ion conductivity (reaching 10-4S cm < -1 > at 50 ℃) and good mechanical strength (2Mpa), and can be used as a solid electrolyte membrane, a functional binder of a positive electrode and an SEI (solid electrolyte interphase) membrane on the surface of a lithium negative electrode. The solid electrolyte of the bulk plasticized polymer prepared by the invention has the advantages of simple and rapid synthesis, low raw material cost, high interface compatibility, strong lithium ion conductivity, good mechanical strength and the like.
Patent application No. CN201811204482.7 discloses a solid polymer electrolyte for lithium ion batteries and applications thereof. The preparation method of the solid polymer electrolyte for the lithium ion battery comprises the following steps: dispersing a monomer 1, a monomer 2, a monomer 3, a cross-linking agent and lithium salt in a solvent to obtain a mixed solution; and thermally initiating polymerization of the mixed solution to obtain the polymer. According to the invention, different monomers and cross-linking agents are subjected to thermal initiation polymerization under the condition of no initiator, so that the adverse effect of the introduction of the initiator on the performance of the lithium ion battery is avoided, and the solid polymer electrolyte suitable for the lithium battery is prepared. Meanwhile, the polymeric monomer contains an ascorbic acid group, and the group can react on the surface of an electrode in the charge-discharge process to generate an SEI film, so that the polymer electrolyte and the lithium battery electrode are tightly bonded together, and the problem of poor compatibility between the solid electrolyte and an electrode material is solved.
Patent application No. CN201811205185.4 discloses a solid polymer electrolyte and its application. The preparation of the solid polymer electrolyte comprises: dispersing a monomer 1, a monomer 2, a monomer 3, a cross-linking agent and lithium salt in a solvent to obtain a mixed solution; and thermally initiating polymerization of the mixed solution to obtain the polymer. According to the invention, different monomers and cross-linking agents are subjected to thermal initiation polymerization under the condition of no initiator, so that the adverse effect of the introduction of the initiator on the performance of the lithium ion battery is avoided, and the solid polymer electrolyte suitable for the lithium battery is prepared. Meanwhile, the solid polymer electrolyte contains sulfonyl groups, and the sulfonyl groups can react on the surface of an electrode in the charge and discharge processes of a lithium battery to generate an SEI (solid electrolyte interphase) film, so that the polymer electrolyte and the electrode of the lithium battery are tightly bonded together, and the problem of poor compatibility between the solid electrolyte and an electrode material is solved.
Patent application No. CN201911026313.3 discloses a solid electrolyte for a lithium metal negative electrode and a preparation method thereof, wherein the solid electrolyte comprises an organic electrolyte layer and an inorganic electrolyte layer which are integrally arranged, the organic electrolyte layer is pressed with a positive electrode layer, the inorganic electrolyte layer is pressed with a lithium metal negative electrode layer, and an SEI film is formed between the inorganic electrolyte layer and the lithium metal negative electrode layer. The solid electrolyte is used for preparing an organic electrolyte layer by an electrostatic spinning technology, and an inorganic electrolyte layer is formed by a compression molding method, so that the interface resistance between the solid electrolyte layer and a positive electrode layer and the interface resistance between the solid electrolyte layer and a lithium metal negative electrode layer are effectively reduced, and the good conductivity of lithium ions is ensured, so that the prepared lithium battery has excellent cycle performance.
These studies have raised the heat of research on the effect of solid electrolyte on SEI film formation, but the careful study on the electrode/polymer electrolyte interface has greater difficulty than the study on the interfacial behavior of the electrode in a liquid electrolyte because a passivation film formed on the electrode/polymer electrolyte interface is thin and non-uniform, is very sensitive to air and water, and is easily lost, so that the development of a solid electrolyte for in-situ protection of a metallic lithium negative electrode is very important for a solid battery using the metallic lithium negative electrode.
Disclosure of Invention
The invention provides a solid electrolyte for in-situ protection of a lithium metal cathode and a preparation method thereof, aiming at the defects of the prior art.
The method is realized by the following technical scheme:
the first purpose of the invention is to provide a solid electrolyte for in-situ protection of a lithium metal negative electrode, which is a double-salt type solid electrolyte with a negative electrode protective agent and a lithium salt.
Further, the solid electrolyte for in-situ protection of the lithium metal negative electrode comprises the following components in percentage by weight: 5-10% of a negative electrode protective agent, 5-10% of lithium salt, 10-15% of an additive, 10-15% of a plasticizer and the balance of a polymer substrate.
The polymer substrate includes, but is not limited to, any one or more of the following: PEO, PAN, PMMA, PVDF-HFP.
The negative electrode protective agent is LiNO3And LiBOB, and the like.
The lithium salt is LiPF6、LiBF4And LiTFSI.
The additive is any one or more of silicon dioxide nanoparticles, aluminum oxide nanoparticles, micromolecular polymers and garnet type nanoparticles.
The plasticizer is any one or a mixture of succinonitrile and ethylene carbonate.
The solvent is any one or more of NN '-dimethylformamide, NN' -dimethylacetamide, tetrahydrofuran and acetonitrile.
The second purpose of the invention is to provide a preparation method of the solid electrolyte for in-situ protection of the lithium metal negative electrode, which comprises the following steps:
1) uniformly mixing a polymer substrate, a negative electrode protective agent, lithium salt, an additive, a plasticizer and a solvent, and stirring at the constant temperature of 55-65 ℃ until the solution is clear and transparent;
2) casting the uniformly mixed solution on a glass plate, and drying in a constant-temperature oven at 70-90 ℃ to obtain a pre-dried polymer electrolyte film;
3) and (3) placing the pre-dried polymer electrolyte film in a vacuum oven at the temperature of 48-56 ℃ to dry for more than or equal to 4 hours.
The solvent is used in an amount 2-3 times that of the polymer substrate.
Has the advantages that:
the solid electrolyte can ensure the continuous generation of an SEI film on the surface of the lithium metal negative electrode, inhibit the growth of dendrites in the lithium negative electrode and improve the cycling stability of the lithium metal negative electrode.
The solid electrolyte contains the negative electrode protective agent and the lithium salt which are released in the process of charging and discharging of the solid battery, the negative electrode protective agent can effectively prevent metal lithium from being converted into lithium dendrites, the stability of the lithium negative electrode is improved, the overall mechanical strength and the thermal stability of the polymer are further improved, and a stable interface is formed between the electrolyte and the metal lithium.
The invention optimizes the carrier concentration in the polymer electrolyte by controlling the dosage of lithium salt.
The invention selects succinonitrile or ethylene carbonate as the plasticizer, can strengthen the strength of the SEI film, prevent the breakage of the SEI film, control the dosage of the plasticizer, reduce the glass transition temperature and the melting point, facilitate the migration of ions and improve the ionic conductivity.
The currently used negative electrode protective agent is mainly LiNO3And LiBOB: LiNO3 is a lithium salt containing N element, and is matched with a fluorine-containing lithium salt for use, so that N and F elements required by the growth of an SEI film on the surface of a lithium cathode can be provided, the SEI can continuously and stably grow on the surface of the cathode, and the service life of the cathode is prolonged; and LiBOB is a liquid lithium battery cathode protective agent, promotes the formation of SEI, and can effectively prolong the service life of the lithium metal cathode. And the two lithium metal negative electrode protective agents can promote the stability of an SEI film, contain lithium ions, have larger anion groups and can effectively improve the ionic conductivity of the solid electrolyte. Negative electrode protection in solid electrolyte during cycling of solid lithium batteryThe protecting agent moves to the surface of the negative electrode through charge migration and ion diffusion to react with the negative electrode, so that the protecting agent is protected.
Detailed Description
The following is a detailed description of the embodiments of the present invention, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments are included in the scope of the present invention as claimed in the claims.
Example 1
A solid electrolyte for in-situ protection of a metal lithium cathode is a double-salt solid electrolyte with a cathode protective agent and a lithium salt;
the components of the material by weight percentage are as follows: 5% of a negative electrode protective agent, 5% of lithium salt, 10% of an additive, 10% of a plasticizer and the balance of a polymer substrate;
the polymeric substrate is PEO;
the negative electrode protective agent is LiNO3；
The lithium salt is LiPF6；
The additive is silicon dioxide nano particles;
the plasticizer is succinonitrile;
the solid electrolyte for in-situ protection of the metal lithium cathode is prepared by dissolving the cathode protective agent, lithium salt, additive, plasticizer and polymer substrate in a solvent, and then pouring and drying for the second time;
the solvent was NN' -dimethylformamide, which was used in an amount 2.5 times the amount of the polymer substrate.
Example 2
A solid electrolyte for in-situ protection of a metal lithium cathode is a double-salt solid electrolyte with a cathode protective agent and a lithium salt;
the components of the material by weight percentage are as follows: 10% of a negative electrode protective agent, 10% of lithium salt, 15% of an additive, 15% of a plasticizer and the balance of a polymer substrate;
the polymeric substrate is PEO;
the negative electrode protective agent is LiBOB;
the above-mentionedThe lithium salt being LiBF4；
The additive is garnet-type nanoparticles;
the plasticizer is succinonitrile;
the solid electrolyte for in-situ protection of the metal lithium cathode is prepared by dissolving the cathode protective agent, lithium salt, additive, plasticizer and polymer substrate in a solvent, and then pouring and drying for the second time;
the solvent is NN' -dimethylacetamide, and the dosage of the solvent is 2 times of that of the polymer substrate.
Example 3
A method for preparing a solid electrolyte for in-situ protection of a lithium metal negative electrode comprises the following steps:
1) uniformly mixing a polymer substrate, a nitrogenous nitrated lithium salt, a fluorine-containing lithium salt, an additive, a plasticizer and a solvent, and stirring at the constant temperature of 55-65 ℃ until the solution is clear and transparent;
2) casting the uniformly mixed solution on a glass plate, and drying in a constant-temperature oven at 70-90 ℃ to obtain a pre-dried polymer electrolyte film;
3) and (3) placing the pre-dried polymer electrolyte film in a vacuum oven at the temperature of 48-56 ℃ to dry for more than or equal to 4 hours.
Comparative example 1
The solid electrolyte for in-situ protecting the metallic lithium negative electrode is a lithium salt-containing solid electrolyte;
the components by weight percentage are as follows: 7% of fluorine-containing lithium salt, 8% of additive, 7% of plasticizer and the balance of polymer substrate;
the polymeric substrate is PEO;
the fluorine-containing lithium salt is LiPF6；
The additive is silicon dioxide nano particles;
the plasticizer is succinonitrile;
the solid electrolyte for in-situ protection of the metal lithium cathode is prepared by dissolving the cathode protective agent, lithium salt, additive, plasticizer and polymer substrate in a solvent, and then pouring and drying for the second time;
the solvent is NN' -dimethylformamide, and the dosage of the solvent is 3 times of that of the polymer substrate;
the button solid-state battery is assembled by adopting a 622 ternary positive electrode as a positive electrode and a lithium metal negative electrode as a negative electrode, and the solid electrolytes of the embodiment 1 and the comparative example 1 are respectively adopted as electrolytes, and the cycle performance test is carried out on the button solid-state battery under the following test conditions: cycling at a rate of 1C at 25 ℃, and testing voltage is 3-4.2V; the results are shown in FIGS. 1 and 2;
fig. 1 shows the cycling performance of the assembled button solid state cell of example 1; fig. 2 shows the cycling performance of the assembled button solid state cell of comparative example 1; as can be seen from fig. 1 and 2: the solid-state battery of example 1 had a capacity retention of about 60% and the battery of comparative document 1 had a capacity retention of about 40% at 150 cycles.
Claims (9)
1. The solid electrolyte for in-situ protection of the metal lithium negative electrode is characterized by being a double-salt solid electrolyte with a negative electrode protective agent and a lithium salt.
2. The solid state electrolyte for in situ protection of a lithium metal anode of claim 1, wherein the solid state electrolyte for in situ protection of a lithium metal anode comprises the following components in weight percent: 5-10% of a negative electrode protective agent, 5-10% of lithium salt, 10-15% of an additive, 10-15% of a plasticizer and the balance of a polymer substrate.
3. The solid-state electrolyte for in-situ protection of a lithium metal anode of claim 1 or 2, wherein the polymer substrate includes, but is not limited to, any one or more of the following: PEO, PAN, PMMA, PVDF-HFP.
4. The solid-state electrolyte for in-situ protection of a lithium metal anode of claim 1 or 2, wherein the anode protectant is LiBOB, LiNO3。
5. The solid-state electrolyte for in-situ protection of a lithium metal anode of claim 1 or 2, wherein the lithium salt is LiPF6、LiBF4And LiTFSI.
6. The solid-state electrolyte for in-situ protection of the lithium metal negative electrode as claimed in claim 1 or 2, wherein the additive is any one or more of silica nanoparticles, aluminum oxide nanoparticles, small molecule polymer, and garnet-type nanoparticles.
7. The solid-state electrolyte for in-situ protection of a lithium metal anode according to claim 1 or 2, wherein the plasticizer is any one or a mixture of succinonitrile and ethylene carbonate.
8. The solid electrolyte for in-situ protection of the lithium metal anode according to claim 1 or 2, wherein the solvent is any one or more of NN '-dimethylformamide, NN' -dimethylacetamide, tetrahydrofuran and acetonitrile.
9. The method of preparing a solid state electrolyte for in situ protection of a lithium metal anode of claim 1 or 2, comprising the steps of:
1) uniformly mixing a polymer substrate, a negative electrode protective agent, lithium salt, an additive, a plasticizer and a solvent, and stirring at the constant temperature of 55-65 ℃ until the solution is clear and transparent;
2) casting the uniformly mixed solution on a glass plate, and drying in a constant-temperature oven at 70-90 ℃ to obtain a pre-dried polymer electrolyte film;
3) and (3) placing the pre-dried polymer electrolyte film in a vacuum oven at the temperature of 48-56 ℃ to dry for more than or equal to 4 hours.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112701348A (en) * | 2020-12-28 | 2021-04-23 | 南方科技大学 | Polymer solid electrolyte, all-solid-state lithium battery and preparation method thereof |
| CN113346051A (en) * | 2021-06-04 | 2021-09-03 | 天津中电新能源研究院有限公司 | Preparation method of metal lithium surface protection layer |
| CN113346052A (en) * | 2021-06-04 | 2021-09-03 | 天津中电新能源研究院有限公司 | Method for protecting surface of metal lithium |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107078344A (en) * | 2014-10-31 | 2017-08-18 | 株式会社Lg 化学 | Lithium-sulfur battery and manufacturing method thereof |
| CN107819152A (en) * | 2017-11-03 | 2018-03-20 | 河南华瑞高新材料有限公司 | A kind of reference electrolyte and preparation method that can improve lithium-sulfur cell cycle performance |
| WO2018225434A1 (en) * | 2017-06-08 | 2018-12-13 | 国立研究開発法人物質・材料研究機構 | Non-aqueous electrolytic solution for lithium air batteries, and lithium air battery using same |
| CN109037764A (en) * | 2018-08-29 | 2018-12-18 | 浙江工业大学 | A kind of preparation method of the solid electrolyte of stable lithium an- ode |
| CN109830746A (en) * | 2019-01-29 | 2019-05-31 | 蜂巢能源科技有限公司 | Solid electrolyte and its application and cathode material and its preparation method and application |
| CN111063863A (en) * | 2019-12-19 | 2020-04-24 | 电子科技大学 | A kind of metal lithium composite negative electrode material and preparation method and application thereof |
| CN111129593A (en) * | 2019-12-25 | 2020-05-08 | 广东工业大学 | A kind of additive of secondary lithium metal battery electrolyte, electrolyte and preparation method |
-
2020
- 2020-08-19 CN CN202010838617.6A patent/CN111969247A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107078344A (en) * | 2014-10-31 | 2017-08-18 | 株式会社Lg 化学 | Lithium-sulfur battery and manufacturing method thereof |
| WO2018225434A1 (en) * | 2017-06-08 | 2018-12-13 | 国立研究開発法人物質・材料研究機構 | Non-aqueous electrolytic solution for lithium air batteries, and lithium air battery using same |
| CN107819152A (en) * | 2017-11-03 | 2018-03-20 | 河南华瑞高新材料有限公司 | A kind of reference electrolyte and preparation method that can improve lithium-sulfur cell cycle performance |
| CN109037764A (en) * | 2018-08-29 | 2018-12-18 | 浙江工业大学 | A kind of preparation method of the solid electrolyte of stable lithium an- ode |
| CN109830746A (en) * | 2019-01-29 | 2019-05-31 | 蜂巢能源科技有限公司 | Solid electrolyte and its application and cathode material and its preparation method and application |
| CN111063863A (en) * | 2019-12-19 | 2020-04-24 | 电子科技大学 | A kind of metal lithium composite negative electrode material and preparation method and application thereof |
| CN111129593A (en) * | 2019-12-25 | 2020-05-08 | 广东工业大学 | A kind of additive of secondary lithium metal battery electrolyte, electrolyte and preparation method |
Non-Patent Citations (2)
| Title |
|---|
| WENFENG LIANG, YUNFAN SHAO, YU-MING CHEN, AND YU ZHU: "A 4 V Cathode Compatible, Superionic Conductive Solid Polymer Electrolyte for Solid Lithium Metal Batteries with Long Cycle Life", 《ACS APPLIED ENERGY MATERIALS》 * |
| 陈玉华，姚宏颖，崔海波: "《新型清洁能源技术》", 31 January 2019, 知识产权出版社 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112701348A (en) * | 2020-12-28 | 2021-04-23 | 南方科技大学 | Polymer solid electrolyte, all-solid-state lithium battery and preparation method thereof |
| CN112701348B (en) * | 2020-12-28 | 2024-01-12 | 南方科技大学 | Polymer solid electrolyte, all-solid lithium battery and preparation method thereof |
| CN113346051A (en) * | 2021-06-04 | 2021-09-03 | 天津中电新能源研究院有限公司 | Preparation method of metal lithium surface protection layer |
| CN113346052A (en) * | 2021-06-04 | 2021-09-03 | 天津中电新能源研究院有限公司 | Method for protecting surface of metal lithium |
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